1. Field of the Invention
The present invention relates to a display panel, and more particularly, to a display panel with high quality display.
2. Description of the Prior Art
Please refer to FIG. 1. In the conventional active matrix type liquid crystal display (LCD), each pixel of a single-gate circuit structure includes a thin-film transistor (TFT) 10. Agate electrode of the TFT 10 is connected to a horizontal gate line 12, and a source electrode of the TFT 10 is connected to a vertical data line 14. A drain electrode of the TFT 10 is connected to a pixel electrode, and the TFTs 10 in two adjacent columns are respectively connected to corresponding data lines 14.
The following description introduces a basic operating method of the conventional circuit structure. Ina same horizontal gate line 12, the gate electrodes of the TFTs 10 are electrically connected to each other, so that voltages respectively applied to the TFTs are related to each other. If a large enough positive voltage is applied to a gate line 12, all TFTs 10 connected to this gate line 12 will be turned on. The pixel electrodes disposed along this gate line 12 are respectively electrically connected to the vertical data lines 14, and corresponding data signals are transferred into the vertical data lines 14 so as to charge the pixel electrodes to appropriate voltages. Next, a large enough negative voltage is applied to turn off the TFTs 10 until the next data signals are written into the TFTs 10 again. During the intervening time between transferring the data signals and transferring the next data signals, the electric charges are stored on the liquid crystal capacitor. The next horizontal gate line 12 is then started, and the corresponding data signals are transferred into the data lines 14. The data signals of a whole frame can be written into the TFTs 10 in sequence according to the above-mentioned method. After that the process of transferring the data signals can be performed again from the first gate line.
Because the plurality of data lines match source chips in the above-mentioned single gate circuit structure, more source chips should be used, and the cost of the display panel is rather high. In order to reduce the cost, a dual-gate circuit structure is provided, as shown in FIG. 2. TFTs 16 in two adjacent columns share the same data line 18. The number of the data lines 18 can be reduced, and the number of the source chips is also reduced. Accordingly, the manufacturing cost of the display panel is reduced.
However, as shown in FIG. 3, in the circuit layout of the above-mentioned prior art, the gate line 20 and the common line 22 are formed by the same metal layer and they are substantially close to each other. In the manufacturing process, if particles are dropped onto the substrate inadvertently, the gate lines 20 and the common lines 22 easily can be short-circuited after the manufacturing process, causing dark stripes or bright stripes on the display panel. In addition, the aperture ratio of the whole display panel is reduced. Two electrodes 24 disposed between adjacent gate lines and between adjacent data lines 18 are respectively display regions of two pixels, and the common line 22 overlaps a transmissive region of the electrode layer 24. Therefore, an area of the transmissive region of the electrode layer 24 deducting the metal layer of the common line 22 is reduced and the aperture ratio of the whole display panel is decreased.
According to the above-mentioned problems, the present invention provides a display panel with a high quality display to solve the problems generated in the prior art.